Injector for a subcutaneous insertion set

• US 6,093,172 A
• Filed: 12/31/1997
• Issued: 07/25/2000
• Est. Priority Date: 02/05/1997
• Status: Expired due to Term

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Minimed, Inc. (Medtronic Plc)
• Inventors: Marano, April A., Funderburk, Jeffery V., Field, Jeffrey F.
• Primary Examiner(s): Stright, Ronald
• Assistant Examiner(s): BIANCO, PATRICIA
• Application Number:
  US09/002,303
• Time in Patent Office: 937 Days
• Field of Search: 604/131, 604/134, 604/135, 604/136, 604/137, 604/138, 604/156, 604/157, 604/187, 604/218, 604/220
• US Class Current: 604/135
• CPC Class Codes: A61M 2005/1581 Right-angle needle-type devices
• CPC Class Codes: A61M 2005/1583 Needle extractors
• CPC Class Codes: A61M 2005/1585 Needle inserters
• CPC Class Codes: A61M 5/158 Needles for infusions; Accessories therefor, e.g. for inserting infusion needles, or for holding them on the body

Abstract

An injector is provided for automatic placement of a subcutaneous insertion set such as an infusion set or the like used for delivering a selected medication to a patient. The injector comprises a spring-loaded plunger having a head for receiving and supporting the insertion set in a position for placement of a medical insertion needle through the skin of a patient at a selected insertion site. The plunger head includes a safety lock mechanism for engaging and retaining the insertion set during spring-loaded advancement with a controlled force and speed toward the patient'"'"'s skin to transcutaneously place the insertion needle. When the plunger head reaches a fully advanced position, with the insertion set placed on the patient, the insertion set is releasible from the safety lock mechanism with minimal force to permit quick and easy separation of the injector. Alternately, in some embodiments, the injector can be displaced away from the patient'"'"'s skin to separate the insertion needle from the insertion set, while leaving the insertion set in place on the patient.

Claims

1. An injector for transcutaneously placing an insertion needle of a subcutaneous insertion set through the skin of a patient, comprising:

a barrel having an elongated base formed therein;

a plunger slidably received within the bore for movement between an advanced position and a retracted position, the plunger including a support structure for receiving and supporting the insertion set in a position with the insertion needle oriented for transcutaneous placement upon movement of the plunger from the retracted position to the advanced position, wherein the plunger is substantially incapable of delivering a fluid from the insertion set upon movement from the retracted position to the advanced position; and

a drive for urging the plunger with a controlled force and speed from the retracted position toward the advanced position to transcutaneously place the insertion needle,

wherein the support structure is removable from the insertion set while maintaining the transcutaneous placement of the insertion needle.

2. The injector of claim 1, wherein the barrel has a forward end defining a generally planar surface for placement against the skin of a patient with the barrel in a predetermined orientation relative to the patient'"'"'s skin.

3. The injector of claim 2, wherein the plunger and the insertion needle supported thereby are substantially retracted within the bore when the plunger is in the retracted position, the barrel having at least one slot formed therein and extending longitudinally from the forward end thereof.

4. The injector of claim 2, wherein the insertion set comprises at least one outwardly radiating base wing for securing the insertion set to the patient'"'"'s skin, and at least one outwardly radiating coupling element, the barrel having at least one cut out and at least one slot formed therein to extend longitudinally from the forward end thereof for respective slide-fit reception of the base wing and coupling element.

5. The injector of claim 1, further including a trigger for actuating the drive.

6. The injector of claim 5, wherein the trigger includes a trigger actuator for fingertip depression to actuate the drive for movement of the plunger from the retracted position to the advanced position.

7. The injector of claim 6, wherein the drive comprises spring means for spring-loaded movement of the plunger from the retracted position to the advanced position.

8. The injector of claim 5, wherein the trigger includes lock means for releasibly locking the plunger in the retracted position.

9. The injector of claim 1, wherein the barrel and the plunger include cooperatively engageable track means for guiding movement of the plunger between the advanced and retracted positions while retaining the plunger against rotation relative to the barrel.

10. The injector of claim 1, wherein the insertion needle is provided as part of an insertion set, and further wherein the plunger comprises a plunger head having a recess formed therein for mated slide-fit reception of at least a portion of the insertion set.

11. The injector of claim 10, wherein the plunger head recess comprises a laterally open undercut recess.

12. The injector of claim 10, wherein the plunger head further includes safety retainer means for retaining the insertion needle on the plunger head during movement from the retracted position to the advanced position, the safety retainer means permitting separation of the insertion needle from the plunger head when the plunger head is in the advanced position.

13. The injector of claim 12, wherein the safety retainer means comprising at least one safety lock arm having one end pivotally mounted on the plunger head and an opposite end defining a lock finger for releasibly engaging the insertion needle, the barrel retaining said safety lock arm against outward pivoting motion relative to the plunger head recess when the plunger is moved from the advanced position, the safety lock arm being in a position relative to the barrel for permitting outward pivoting movement with respect to the plunger head recess when the plunger is in the advanced position.

14. The injector of claim 13, wherein the at least one safety lock arm comprises a pair of safety lock arms each having one end pivotally mounted on the plunger and an opposite end defining a lock finger for releasibly engaging the insertion needle.

15. The injector of claim 14, wherein the barrel has a forward end with a pair of open-ended cut outs formed therein, the safety lock arms being disposed generally within said cut outs when the plunger is in the advanced position.

16. The injector of claim 12, wherein the safety retainer means comprises a radially inwardly projecting rim of noncircular shape formed generally at a leading end of the plunger head, the rim engaging the insertion needle when the needle is generally aligned coaxially within the plunger head and permitting release of the needle when the needle is angularly oriented relative to the plunger head.

17. The injector of claim 16, wherein the rim has a generally elliptical shape.

18. An injector for transcutaneously placing an insertion needle of a subcutaneous insertion set through the skin of a patient, comprising:

a barrel having an elongated bore formed therein;

a plunger slidably received within the bore for movement between an advanced position and a retracted position, the plunger including a support structure for mated slide-fit reception and support of the insertion set in a position with the insertion needle oriented for transcutaneous placement upon movement of said plunger from the retracted position to the advanced position, wherein the plunger is substantially incapable of delivering a fluid from the insertion set upon movement from the retracted position to the advanced position;

a spring for urging said plunger toward the advanced position; and

a trigger for releasibly retaining the plunger in the retracted position, the trigger being operable to release the plunger for spring-loaded movement with a controlled force and speed toward the advanced position,

wherein the support structure is removable from the insertion set while maintaining the transcutaneous placement of the insertion needle.

19. The injector of claim 18, wherein the plunger further including safety retainer means for retaining the insertion set on the advanced position, the safety retainer means permitting the removal of the insertion set from the plunger when the plunger is in the advanced position.

20. The injector of claim 18, wherein the barrel has a forward end defining a generally planar surface of placement against the skin of a patient with the barrel in a predetermined orientation relative to the patient'"'"'s skin.

21. The injector of claim 18, wherein the barrel and the plunger include cooperatively engageable track means for guiding movement of the barrel and the plunger between the advanced and retracted positions while retaining the barrel and the plunger against rotation relative to the barrel and the plunger.